Hallowell, ME 04227 Frost Dates
Hallowell, ME: when does the frost end?
Around 05/04 is the usual last spring frost, about 249 days away. Fall's first freeze usually shows up around 10/06, roughly 155 days after the last spring frost.
Hallowell sits in USDA Zone 5a (-20 to -15°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
With roughly 6 weeks until Hallowell's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 05/04 isn't a guarantee
05/04 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/23 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/17 and only about 1 year in 10 sees frost after that.
Hallowell against the rest of the dataset
About 155 days separate Hallowell's last and first frost, putting it 33,990 of 40,283 ZIP codes nationally. Within ME, it ranks 204 of 456.
Learn more
Before leaning on 04227's figures: zone vs. frost date explains why Zone 5a and Hallowell's frost date answer different questions, while the frost range explains how to read the range around Hallowell's dates instead of trusting one.